Reinforced hose

ABSTRACT

An improved reinforced hose for conducting fluids and gases, and a method of manufacturing that hose, are disclosed herein. The improved reinforced hose includes an interior tube having an inner bore and an outer surface. The improved reinforced hose also includes an outer covering disposed directly about the outer surface of the interior tube. Such outer covering includes one or more layers of plastic threads, which are formed by disposing a plastic substance about core material.

FIELD OF THE INVENTION

The present invention relates to an improved reinforced hose forconducting fluids and gases therethrough and a method for manufacturingsuch a hose. More particularly, the present invention relates to areinforced hose that possesses several advantageous attributes--such as,improved flexibility, increased resistivity to internal pressure andrupture, simplified manufacturing methods, decreased manufacturingcosts, decreased weight, and increased resistance to corrosion--relativeto conventional reinforced hoses.

BACKGROUND OF THE INVENTION

Presently, many different types and constructions of hoses are known.Some hoses are simple ducts or tubes manufactured from materials such asrubber or plastic. However, such hoses are unable to withstandrelatively high internal pressures resulting from the conduction offluids or gases through the hoses at high velocities. To withstand highinternal pressures, reinforced hoses may be employed.

Certain conventional reinforced hoses apply a braided layer of nylon orvarious metal wires about a tube. Hoses reinforced with nylon haverelatively low resistances to high internal pressures. Hoses reinforcedwith aluminum are similarly unable to resist relatively high pressures.Furthermore, aluminum reinforced hoses are highly susceptible tocorrosion, especially when in the presence of acids or detergents.Because of these and other disadvantages, nylon and aluminum reinforcedhoses are only used in limited applications.

Hoses reinforced with stainless steel, due in part to their relativelyhigh resistance to pressures, have enjoyed more commercial success thantheir nylon and aluminum counterparts. While stainless steel reinforcedhoses are able to withstand higher pressures than aluminum and nylonreinforced hoses, they possess several undesirable attributes. First,such hoses are relatively inflexible. That is, stainless steelreinforced hoses can kink and permanently disfigure if contorted invarious manners. This results in the restriction of flow of liquids orgases through the hose. Second, manufacturing a hose having a metalreinforcement is relatively cumbersome and costly in light of thenecessary difficult task of twisting the metal into a braid about thehose. Third, where stainless steel is used to form the reinforcement,the weight of the reinforced hose is substantial. Fourth, stainlesssteel hoses are susceptible to corrosion under certain conditions.

SUMMARY OF THE INVENTION

It is an object of the present invention to overcome the disadvantagesassociated with conventional reinforced hoses, and provide an improvedreinforced hose for conducting fluids and gases.

It is another object of the present invention to provide an improvedreinforced hose having a higher resistance to internal pressures, andrupture, relative to conventional reinforced hoses.

It is a yet another object of the present invention to provide animproved reinforced hose having an improved flexibility relative toconventional reinforced hoses.

It is a further object of the present invention to provide an improvedreinforced hose that can be made by simplified manufacturing techniquesrelative, to conventional reinforced hoses.

It is another object of the present invention to provide an improvedreinforced hose that can be made by less expensive manufacturingtechniques relative to conventional reinforced hoses.

It is yet another object of the present invention to provide an improvedreinforced hose that is of a lighter weight relative to conventionalreinforced hoses.

It is a further object of the present invention to provide an improvedreinforced hose having an increased resistivity to corrosion relative toconventional reinforced hoses.

In accordance with the present invention, an improved reinforced hosefor conducting fluids or gases is provided. The reinforced hose of thepresent invention includes an interior tube and an outer covering. Theinterior tube has an inner bore, in which fluids are conducted, and anouter surface. The outer covering is disposed directly about the outersurface of the interior tube for reinforcing the interior tube to resistrupture and provide enhanced flexibility, and is comprised of threadsformed by disposing a plastic substance about a core material. Suchplastic threads are formed into one or more braided layers. Preferably,the outer covering includes a single braided layer of plastic threads.That is, no intermediate layers are preferably interposed between theinterior tube and the outer covering.

According to one aspect of the present invention, the plastic substanceand core material employed to form the plastic threads are specificallyselected. Preferably, the plastic substance comprises a vinyl orpolyvinyl substance, whereas the core material comprises a plastic orpolymeric material. More preferably, the plastic substance comprisespolyvinyl chloride, whereas the core material comprises polyesterfilaments. The interior tube may, for example, compriseethylene-propylene-compound diene, acrylonitrile-butadiene or Teflon™,which is a synthetic resinous fluorine containing polymers in form ofmolding and extruding compositions, solutions, and emulsions orpolytetrafluoroethylene coating in the nature of paints and varnishes.

According to another aspect of the present invention, the threads areformed into distinct strands that are interwoven to form a braidedlayer. Preferably, each strand includes less than seven (7) threads.More preferably, each strand includes between about two (2) and five (5)threads. Most preferably, each strand includes between about two (2) andthree (3) threads.

According to yet another aspect of the present invention, the gauge ofthe threads used to form the outer covering of the improved reinforcedhose are empirically selected based on various factors. Preferably, thegauge of the threads ranges from about 0.005 of an inch to 0.060 of aninch. More preferably, the gauge of the threads ranges from about 0.010of an inch to 0.040 of an inch. Most preferably, the gauge of thebraided threads ranges from about 0.015 of an inch to 0.030 of an inch.

According to a further aspect of the present invention, the tension withwhich the outer covering is disposed about the interior tube is alsoempirically selected based on various factors. Preferably, such tensionranges from about one to two pounds. More preferably, such tension isapproximately 1.5 pounds.

In accordance with the present invention, a method of manufacturing theimproved reinforced hose is disclosed. Such method includes: (1)providing an interior tube having an inner bore, in which fluids areconducted, and an outer surface; (2) disposing a plastic substance abouta core material to form plastic threads; and (3) interweaving theplastic threads about the outer surface of the interior tube to form oneor more braided layers that reinforce the interior tube.

According to one aspect of the method of the present invention, theplastic substance is disposed about the core material by an extrusiontechnique.

Other objects, advantages and meritorious aspects of the presentinvention will be understood from the description of the preferredembodiments, appended claims and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention may be better understood from the followingdetailed description of preferred embodiments of the present inventionwith reference to the accompanying drawings, in which:

FIG. 1 is a cross-sectional view of an improved reinforced hose;

FIG. 1A is an enlarged sectional view of an outer covering of theimproved reinforced hose of FIG. 1;

FIG. 1B is a perspective view of the improved reinforced hose of FIG. 1;

FIG. 2 is a cross-sectional view of a thread of the outer covering ofFIG. 1; and

FIG. 3 illustrates an assembly for manufacturing the reinforcement hoseof FIG. 1.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE PRESENT INVENTION

Set forth below is a detailed description of preferred embodiments ofthe present invention.

Improved Reinforced Hose

FIG. 1 illustrates a cross-sectional view of an improved reinforced hose100, in accordance with a preferred embodiment of the present invention.

The reinforced hose illustrated in FIG. 1 includes an interior tube 104,having an inner bore 102, in which fluids and/or gases may be conductedtherethrough. The interior tube 104 should be impervious and flexible,and is preferably comprised of a natural or synthetic polymer, copolymeror terpolymer. Selection of the interior tube 104 is based on the typeof fluid or gas being conducted through the inner bore 102. For example,the interior tube 104 may comprise ethylene-propylene-compound diene(EPDM), or another plastic or rubber material, may be used when potablewater is conducted through the inner bore 102. As a further example,acrylonitrile-butadiene may be used to conduct gaseous or petroleumproducts through the inner bore 102. As yet another example, the innertube 104 may comprise Teflon™ when used to conduct chemicals.

An outer covering, generally identified by reference numeral 108, isdisposed directly over, and surrounding, the outer surface of theinterior tube 104. Such outer covering 108 is formed about the interiortube 104 to enable the hose 100 to withstand significant internalpressures through the inner bore 102 of the interior tube 104. Inaccordance with the present invention, the outer covering 108 iscomprised of a plurality of plastic threads. An exemplary plastic thread106 is illustrated in FIG. 1. Such threads 106 are preferably interwovento form a braided layer, or otherwise suitably interlaced together, toform the outer covering 108. To increase the ability of the hose 100 towithstand high internal pressures, the outer covering 108 may includemore than one braided layer formed about the interior tube 104. However,for most applications, a single braided layer of interwoven threads 106is sufficient to provide the necessary reinforcement.

It should be appreciated that, in accordance with the present invention,no intermediate layers should be interposed between the interior tube104 and the outer covering 108. Furthermore, no layers are preferablydisposed above and surrounding the outer covering 108.

The flexibility of the reinforced hose 100 establishes a union betweenlines and pipes in an efficient and facilitated manner without having toresort to the use of conventional pipes and tubing. The reinforced hose100 disclosed herein is especially applicable for use in the supply offluids. For example, the hoses may be employed to distribute water todomestic sanitary appliances, such as toilets and sinks. However, it mayalso be used to supply gas. For example, the present invention may beused to supply gas to various domestic appliances, such as heaters,stoves and dryers.

FIG. 1A illustrates an enlarged sectional view of the outer covering 108of the improved reinforced hose 100 of FIG. 1, in accordance with apreferred embodiment of the present invention. As illustrated in FIG. 1,the outer covering 108 of the reinforced hose 100 includes multipleplastic threads 106 that are grouped or united into strands 120. Thestrands 120 are preferably braided about the interior tube 104 pursuantto the "two over, two under" method of braiding. Such method allows forthe threads 106 included in each strand 120 to flatten out during thebraiding operation and form rounded curves so that sharp bends areavoided.

FIG. 1B illustrates a perspective view of the improved reinforced hose100 of FIG. 1, in accordance with a preferred embodiment of the presentinvention. As illustrated in FIG. 1B, the reinforced hose 100 isprovided with fittings 110 at both ends of the hose. Such fittings 110are fastened to the reinforced hose 100 by crimping the fittings 110 tothe ends. A set of connection terminals 112, preferably being threadedto mechanically connect each end of the hose 100 to other connectors,are further connected to the fittings 110.

Threads

FIG. 2 illustrates a cross-sectional view of a plastic thread 106 of thereinforced hose 100 of FIG. 1, in accordance with a preferred embodimentof the present invention.

The plastic threads 106, which form the outer covering 108 of theimproved reinforced hose 100, are preferably formed by extruding aplastic substance 204 over a core material 202, as explained in moredetail below. The plastic substance 204 thus forms the exterior of thethreads 106, while the core material 202 forms the interior of thethreads 106. Preferably, the plastic substance 204 comprises a vinyl orpolyvinyl substance. More preferably, the plastic substance 204comprises polyvinyl chloride. Preferably, the core material 202comprises a plastic or polymeric material. More preferably, the corematerial 202 comprises a multi filament polyester material.Alternatively, the core material 202 may be formed from another plasticmaterial, such as nylon.

It should be appreciated that the plastic substance 204 is preferablyextruded individually over the core materials 202. That is, the corematerials 202 are not collectively treated with the plastic substance204. More specifically, the plastic substance 204 is not extruded overthe core material 202 after the core material 202 has been disposedabout the interior tube 104.

Gauges or diameters of the plastic threads 106 have been empiricallyselected in accordance with a preferred embodiment of the presentinvention. Preferably, the plastic threads 106 are formed to possess agauge or diameter ranging from about 0.005 of an inch to about 0.060 ofan inch. More preferably, the plastic threads possess a gauge rangingfrom about 0.010 of an inch to about 0.040 of an inch. Most preferably,the plastic threads possess a gauge ranging from about 0.015 of an inchto about 0.030 of an inch.

Tensions with which the outer covering 108 is disposed about theinterior tube 104 have been empirically selected in accordance with apreferred embodiment of the present invention. Preferably, such tensionis between about 1 to about 2 pounds. More preferably, such tension isapproximately 1.5 pounds. These tension values provide a greaterflexibility and resistance to rupture in the reinforced hose 100 of thepresent invention. Furthermore, these preferred tension values aresignificantly less than the tensions employed in connection withstainless steel and aluminum reinforced hoses.

Values for the portion of the outside surface of interior tube 104 thatis covered by the outer covering 108 (hereinafter referred to as"coverage area") have been empirically selected in accordance with apreferred embodiment of the present invention. Preferably, the coveragearea is between about 75% and 100%. More preferably, the coverage areais between about 90% and 100%. Most preferably, the coverage area isapproximately 95%.

Examples of Improved Reinforced Hose

Table 1, set forth below, provides examples of reinforced hoses 100 madein accordance with a preferred embodiment of the present invention.

                  TABLE 1                                                         ______________________________________                                        Outer                               Outer                                     Diameter of                                                                            Number of           Number Diameter of                               Interior Threads in                                                                              Gauge of  of     Hose with                                 Tube     a Strand  Threads   Strands                                                                              Reinforcement                             ______________________________________                                        .400 inch                                                                              2         0.025     24     0.465 inch                                                   inch                                                       .400 inch                                                                              3         0.020     24     0.465 inch                                                   inch                                                       .470 inch                                                                              2         0.025     24     0.535 inch                                                   inch                                                       .470 inch                                                                              3         0.025     24     0.540 inch                                                   inch                                                       .600 inch                                                                              2         0.025     24     0.645 inch                                                   inch                                                       .840 inch                                                                              3         0.025     24     0.910 inch                                                   inch                                                       ______________________________________                                    

The examples of the present invention listed in Table 2 are based onreinforced hoses, made in accordance with the present invention, thatare currently being marketed by the INDUSTRIAL DE MANGUERAS REFORZADAS,S.A. DE C.V. of Monterrey, Mexico under the trade name "COFLEX VINILO."

Based on several factors--including, the outer diameter of the interiortube 104, the gauge of the threads 106 selected, and the number ofstrands 120 used to form the braided layer--the number of threads 106 ina strand 120 employed in the reinforcement layer 108 is empiricallyselected, in accordance with a preferred embodiment of the presentinvention. In the examples set forth in Table 1, the number of threads106 united in a particular strand 120 were empirically selected based onan outer diameter of the interior tube 104 ranging from 0.400 to 0.800of an inch, a gauge of the threads 106 ranging from 0.020 to 0.025 of aninch, and twenty-four (24) strands used to form the braided layer.Preferably, less than seven (7) threads 106 are included in a strand.More preferably, between about two (2) and five (5) threads 106 areincluded in a strand. Most preferably, between about two (2) and three(3) threads 106 are included in a strand, as indicated in Table 1.

Method of Manufacture

The process of extruding the outer covering 204 over the core material202 to form the plastic threads 106 is the initial step of themanufacturing process. After the plastic substance 204 is extruded overthe core material 202, the resulting thread 106 is cooled to roomtemperature. Such cooling may, for example, be provided by placing thethread 106 under water after extrusion. Thereafter, one or more threadsare united to form a strand 120, which is then wound around a bobbin orspool. As discussed above, the characteristics of the threads 106 in astrand 120--including the number and gauge--are empirically selectedbased on numerous factors, such as the outer diameter of the interiortube 104 and the number of strands 120 used to form a braided layer ofthe outer covering 108.

FIG. 3 illustrates an assembly for manufacturing the reinforcement hoseof FIG. 1 and its associated method, in accordance with a preferredembodiment of the present invention. The assembly 300 illustrated inFIG. 3 includes a series of bobbins 302, about which the plastic threads106 are stored, that are disposed on a platform 304. The bobbins 302,each supplying a strand 120 of threads 106, are operable to rotate abouttheir own axis. An interior tube 104 is directed through an aperture inthe platform 304 and through a guide 306 disposed above the platform304. A motor 308 is mechanically connected to the platform 304 as wellas a pulley 312.

The braiding formed about the interior tube 104 is formed byinterweaving the strand 120 of threads 106 from each bobbin 302 aboutthe outside surface of the interior tube 104. This is accomplished byrotating the platform 304 by motor 308 around the interior tube 104.Each braided layer is therefore formed by the circulation of the bobbins302 around the interior tube 104. As a consequence, the reinforced hose100 is generated.

After braiding, the formed reinforced hose 100 is directed over a secondguide 314, which is maintained in position by arm 316, and towards thepulley 312. The reinforced hose 100 is pulled by the pulley 312 by themotor 308 in synchronization with the rotation of the platform 304. Thepleating machine 310 pulls the reinforced hose 100 from the pulley 312and coils the hose 100 in a spool 318. The hose 100 may then be lateruncoiled from the spool 318, and cut into different lengths. Connectionterminals 112 (illustrated in FIG. 1B) may be placed at either end ofthe hose 100 to enable connection of the hose 100 to various otherconnectors. Such connection terminals 112 may be secured to the ends ofthe hose 100 by fittings 110 using a pneumatic or hydraulic mechanisms,or other techniques known in the art, to ensure that the hose 100 willbe able to resist high pressures and not render leaks.

The aforementioned manufacturing method is inexpensive and simplifiedwhen compared to those employed to manufacture conventional reinforcedhoses, such as hoses reinforced by stainless steel braids. This isprimarily attributable to the fact that the plastic threads 106 have asignificantly greater flexibility and lesser weight than stainless steelwires. Because of such improved resistance, the assembly 300 is able tooperate at significantly higher rates and speeds, than it is capable ofoperating to form the stainless steel braids, since the problem of abroken thread is encountered infrequently. Further, the plastic threads106 of the present invention, unlike aluminum and stainless steel wires,do not require the application of lubricants to the bobbins 302 so as todecrease friction between the metallic wires of conventional reinforcedhoses. Still further, the assembly 300 is not subjected to wear and tearthat it would be if metal wires were used to form the braiding layer.The resulting cost savings of using the plastic threads 106 to form theouter covering, as opposed to stainless steel wires, allows the assembly300 to decrease the cost of manufacturing the reinforced hose.

Comparison with Conventional Hoses

Table 2, sets forth below, provides a comparison of the reinforced hose100 of the present invention with those reinforced by aluminum andstainless steel threads.

                                      TABLE 2                                     __________________________________________________________________________                                             Ability                                             Weight                                                                            Cost of    Detergent &                                                                              to Bend                                     Burst   Per Manufacture                                                                         Corrosion                                                                          Acid       Without                              Thread Pressure                                                                              Meter                                                                             (Base = 1)                                                                          Resistivity                                                                        Resistivity                                                                         Flexibility                                                                        Distortion                           __________________________________________________________________________    Stainless Steel                                                                      1,800-2,000 psi                                                                       0.06 kg                                                                           1.2   Good/                                                                              Good  Good Poor/Good                            (304 Soft Run)           Excellent                                            Aluminum                                                                             1,000-1,200 psi                                                                       0.03 kg                                                                           1.3   Poor/Good                                                                          Poor  Good Poor/Good                            Plastic (PVC)                                                                        2,000-2,200 psi                                                                       0.03 kg                                                                           1.0   Excellent                                                                          Excellent                                                                           Excellent                                                                          Excellent                            __________________________________________________________________________

As seen from Table 2, the improved reinforced hose of the presentinvention, which employs plastic threads 106, is superior when comparedto hoses bearing stainless steel or aluminum reinforcements.Specifically, when compared to the stainless steel and aluminumreinforced hoses, the plastic reinforced hose: (1) possesses a markedlyhigher burst pressure; (2) a weight of approximately half that of astainless steel reinforced hose; (3) a cost of manufacturing (notincluding cost of reinforcements) that is 20% and 30% less than the costof manufacturing stainless steel and aluminum reinforced hoses,respectively; (4) a higher degree of resistivity to corrosion as well asdetergents and acids; (5) a greater degree of flexibility; and (6) theability to bend without causing a permanent distortion in thereinforcement and, in turn, restricting the flow through the hose. Itshould be noted that at current market prices, stainless steel threads(which are generally preferred to aluminum threads because of poorresistivity attributes and relatively low burst pressures) costsignificantly more than the plastic reinforced threads 106. Whenconsidered, this further increases the cost of manufacture relative to aplastic reinforced hose 100.

The present invention is, therefore, well adapted to carry out theobjects and attain the ends and advantages mentioned, as well as othersinherent therein. While presently preferred embodiments of the inventionhave been given for the purposes of disclosure, alternative embodiments,changes and modifications in the details of construction,interconnection and arrangement of parts will readily suggest themselvesto those skilled in the art after having the benefit of this disclosure.This invention is not necessarily limited to the specific examplesillustrated and described above. All such alternative embodiments,changes and modifications encompassed within the spirit of the inventionare included, and the scope of the invention is defined by a properconstruction of the following claims.

What is claimed is:
 1. A flexible hose for conducting fluids or gases,comprising:an interior tube having an inner bore, in which the fluidsare conducted, the interior tube having an outer surface; and at leastone layer of plastic threads braided about the outer surface of theinterior tube, the plastic threads comprising a plastic substance abouta core material, such that the at least one braided layer of plasticthreads reinforces the interior tube to resist rupture and provideenhanced flexibility characteristics.
 2. The flexible hose, according toclaim 1, wherein the plastic substance is a vinyl substance.
 3. Theflexible hose, according to claim 1, wherein the plastic substance ispolyvinyl chloride.
 4. The flexible hose, according to claim 1, whereinthe core material comprises plastic material.
 5. The flexible hose,according to claim 1, wherein the core material comprises polyesterfilaments.
 6. The flexible hose, according to claim 1, wherein a singlebraided layer of plastic threads is disposed directly over the outersurface of the interior tube.
 7. The flexible hose, according to claim1, wherein no intermediate layers are interposed between the outersurface of the interior tube and the at least one braided layer ofplastic threads.
 8. The flexible hose, according to claim 1, wherein theplastic threads are formed by extruding the plastic substance about thecore material.
 9. The flexible hose, according to claim 1, wherein theplastic threads are grouped into distinct strands that are interwoven toform the one or more braided layers of threads.
 10. The flexible hose,according to claim 9, wherein each strand includes less than seven (7)plastic threads.
 11. The flexible hose, according to claim 9, whereineach strand includes between about two (2) and five (5) plastic threads.12. The flexible hose, according to claim 9, wherein each strandincludes between about two (2) and three (3) plastic threads.
 13. Theflexible hose, according to claim 1, wherein the gauge of the plasticthreads ranges from about 0.005 of an inch to 0.060 of an inch.
 14. Theflexible hose, according to claim 1, wherein the gauge of the plasticthreads ranges from about 0.010 of an inch to 0.040 of an inch.
 15. Theflexible hose, according to claim 1, wherein the gauge of the plasticthreads ranges from about 0.015 of an inch to 0.030 of an inch.
 16. Theflexible hose, according to claim 1, wherein the plastic threads aredisposed about the interior tube under tension and wherein the tensionranges from about one to two pounds.
 17. The flexible hose, according toclaim 1, wherein the plastic threads are disposed about the interiortube under tension and wherein the tension is approximately 1.5 pounds.18. The flexible hose, according to claim 1, wherein the interior tubecomprises ethylene-propylene-compound diene.
 19. The flexible hose,according to claim 1, wherein the interior tube comprisesacrylonitrile-butadiene.
 20. The flexible hose, according to claim 1,wherein the interior tube comprises synthetic resinous fluorine.
 21. Amethod for manufacturing a flexible hose for conducting fluids,comprising:providing an interior tube having an inner bore, in whichfluids are conducted, and an outer surface; disposing a plasticsubstance about a core material to form plastic threads; andinterweaving the plastic threads about the outer surface of the interiortube to form one or more braided layers of plastic threads thatreinforce the interior tube.
 22. The method for manufacturing, accordingto claim 21, wherein the plastic substance is disposed about the corematerial by an extrusion technique.
 23. The method for manufacturing,according to claim 21, wherein the core material comprises polyesterfilaments.
 24. The method for manufacturing, according to claim 21,wherein the plastic threads are interwoven about the outer surface ofthe interior tube by circulating the plastic threads around the interiortube.
 25. The flexible hose, according to claim 1, wherein the at leastone layer of threads covers at least 75% of the outer surface of theinterior tube.
 26. The flexible hose, according to claim 1, wherein theat least one layer of threads covers at least 90% of the outer surfaceof the interior tube.
 27. The flexible hose, according to claim 1,wherein the at least one layer of threads covers approximately 95% ofthe outer surface of the interior tube.